Resumo

HERNANDEZ-OCHOA, L. et al. Study of the antibacterial activity of chitosan-based films prepared with different molecular weights including spices essential oils and functional extracts as antimicrobial agents. Rev. Mex. Ing. Quím [online]. 2011, vol.10, n.3, pp.455-463. ISSN 1665-2738.

In this work were evaluated the effect of different molecular weight of chitosan (high, medium and low molecular weight) in the elaboration of antimicrobial films incorporating essenlial oils (AE) and functional extracts (EF) of cumin (Cuminum cyminum L.) and clove (Eugenia caryophyllata) as antimicrobial agents. The Antimicrobial activity of AE and EF were evaluated by determination of Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) against Escherichia coli O157:H7 (ATCC 43888), Salmonella typhimurium, (ATCC 14028), Staphylococcus aureus (ATCC 25923), Bacillus cereus (ATCC 11778) and Listeria monocytogenes. Based on lde MIC/MBC results, essenSrals oils and functional extracts were selected to prepare edible films based on chitosan polymeric structure. The antibacterial effect of the edible films prepared was further evaluated by zone of growth inhibition against the same foodborne pathogens. Results showed that the AE and EF with best CMIs results were: cumin (750 mg/L), clove (500 mg/L), cumin-E₇ (750 mg/L), and clove-E₇ (500 mg/L). It was determined that the films of low molecular weight chitosan with a concentration of 2% of EO of clove and clove E₇ have antimicrobial activity against most strains tested.

Palavras-chave : antibacterial activity; chitosan; molecular weights; essentials oils.